From: Jacob Lifshay <programmerjake@gmail.com>
Date: Tue, 6 Sep 2022 11:39:14 +0000 (-0700)
Subject: clean up remaining comments from fptrans reallocation.
X-Git-Tag: opf_rfc_ls005_v1~650
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=e6130994542942a629b8d1e723f746079e870581;p=libreriscv.git

clean up remaining comments from fptrans reallocation.
---

diff --git a/openpower/power_trans_ops.mdwn b/openpower/power_trans_ops.mdwn
index de0818bea..a3d4a9d5f 100644
--- a/openpower/power_trans_ops.mdwn
+++ b/openpower/power_trans_ops.mdwn
@@ -34,8 +34,6 @@ Entries whose mnemonic ends in `(s)` are in both PO=59 and PO=63.
 
 # DRAFT List of 2-arg opcodes
 
-FIXME(programmerjake): reallocate and convert to X-FORM
-
 These are X-Form, recommended Major Opcode 63 for full-width
 and 59 for half-width (ending in s).
 
@@ -44,13 +42,7 @@ and 59 for half-width (ending in s).
 | NN |FRT | FRA | FRB | 1xxxx011xx  |Rc| transcendental | X-Form  |
 | NN |FRT | FRA | RB  | 1xxxx011xx  |Rc| transcendental | X-Form  |
 
-As shown in Power ISA 3.1 Book III Appendix D Table 28 p1190
-and Table 23 p1368,
-Major Opcode 63 has room
-for 9 A-Form 5-bit XO instructions,
-Major Opcode 59 has 11 5-bit XO instructions,
-with some overlap leading to a partially orthogonal
-set across full and half width.
+Recommended 10-bit XO assignments:
 
 | opcode     | Description                             | Major 59 and 63 | bits 16..20 |
 |------------|-----------------------------------------|-----------------|-------------|
@@ -64,12 +56,11 @@ set across full and half width.
 
 # DRAFT List of 1-arg transcendental opcodes
 
-FIXME(programmerjake): reallocate
-
-These are X-Form, and are identical in Special Registers Altered to `fsqrt`.
+These are X-Form, and are mostly identical in Special Registers Altered to
+`fsqrt` (the exact fp exceptions they can produce differ).
 Recommended Major Opcode 63 for full-width and 59 for half-width (ending in s).
 
-Special Registers Altered:
+Special Registers Altered (FIXME: come up with correct list):
 
     FPRF FR FI FX OX UX XX
     VXSNAN VXIMZ VXZDZ
@@ -79,7 +70,7 @@ Special Registers Altered:
 | -- | -- | --- | --- | ----------  |--| ----      | ------- |
 | NN |FRT | /// | FRB  | 1xxxx011xx |Rc| transcendental | X-Form  |
 
-Recommended 10-bit XO with the low 5 LSBs 01100:
+Recommended 10-bit XO assignments:
 
 | opcode     | Description              | Major 59 and 63 |
 |------------|--------------------------|-----------------|
@@ -101,9 +92,8 @@ Recommended 10-bit XO with the low 5 LSBs 01100:
 
 # DRAFT List of 1-arg trigonometric opcodes
 
-FIXME(programmerjake): reallocate
-
-These are X-Form, and are identical in Special Registers Altered to `fsqrt`.
+These are X-Form, and are mostly identical in Special Registers Altered to
+`fsqrt` (the exact fp exceptions they can produce differ).
 Recommended Major Opcode 63 for full-width and 59 for half-width (ending in s)
 
 Special Registers Altered:
@@ -116,7 +106,7 @@ Special Registers Altered:
 | -- | -- | --- | --- | ----------  |--| ----      | ------- |
 | NN |FRT | /// | FRB  | 1xxxx011xx |Rc| trigonometric | X-Form  |
 
-Recommended 10-bit XO with the low 5 LSBs 01101 to 01111:
+Recommended 10-bit XO assignments:
 
 | opcode      | Description              | Major 59 and 63  |
 |-------------|--------------------------|------------------|